1. Field of the Disclosure
This disclosure relates to a connector and particularly but not exclusively relates to a connector for a downhole tubular.
2. Background Art
GB2435059 discloses a connector for selectively connecting a top drive assembly to a downhole tubular, for example a drill string or casing string. (GB2435059, GB2457287, GB2457288, GB2457317, WO2009/098482, WO2009/098478, WO2009/098473, WO2009/098474, US20070181346A1, US20090200038A1, US2009205827A1, US2009205836A1, US2009205837A1, FR0700899 and CA2577542 are incorporated herein by reference.) One embodiment of a connector disclosed therein comprises an extendable portion with a seal disposed at a distal end of the extendable portion. The seal may engage with the downhole tubular when the extendable portion is extended, thereby greatly reducing the time to fluidically connect and disconnect the downhole tubular from the top drive assembly. The seal may, for example, but not limited to, comprise a cup seal or an inflatable seal and the seal may be adapted for placement within the bore of a downhole tubular, e.g., the seal may contact the inner wall of the downhole tubular.
In the case of a downhole tubular 2 with a tapered box connection 4, as shown in FIG. 1a, the seal may be at least partially guided into the bore 6 of the downhole tubular by the tapered box connection, e.g., contact the inner threaded wall of the box connection. As illustrated with a downhole tubular 12 with a double shouldered box connection 14 in FIG. 1b, a seal may impinge on an internal shoulder 18 (e.g., a shoulder perpendicular to the longitudinal axis of the connection) between a threaded portion 20 and the bore 16 of the downhole tubular 12. Such an impingement of a seal on an internal shoulder (e.g., 18 in FIG. 1b) and/or contact with the inner threaded wall of a box connection (e.g., in FIG. 1a or 1b) may damage and/or increases the wear rate of the seal, thereby reducing its life and increasing the risk of a seal failure. Furthermore, the impingement may also prevent the seal from being disposed (e.g., landing) in the bore 16 altogether.
The present disclosure therefore seeks to address these issues.